Class Boolean
java.lang.Object
java.lang.Boolean
- All Implemented Interfaces:
Serializable,Comparable<Boolean>,Constable
The
Boolean class is the wrapper class for values of the primitive
type boolean. An object of type Boolean contains a
single field whose type is boolean.
In addition, this class provides many methods for
converting a boolean to a String and a
String to a boolean, as well as other
constants and methods useful when dealing with a
boolean.
This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.
- Since:
- 1.0
- See Also:
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Field Summary
Fields -
Constructor Summary
ConstructorsConstructorDescriptionBoolean(boolean value) Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor.Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. -
Method Summary
Modifier and TypeMethodDescriptionbooleanReturns the value of thisBooleanobject as a boolean primitive.static intcompare(boolean x, boolean y) Compares twobooleanvalues.intCompares thisBooleaninstance with another.Returns anOptionalcontaining the nominal descriptor for this instance.booleanReturnstrueif and only if the argument is notnulland is aBooleanobject that represents the samebooleanvalue as this object.static booleangetBoolean(String name) Returnstrueif and only if the system property named by the argument exists and is equal to, ignoring case, the string"true".inthashCode()Returns a hash code for thisBooleanobject.static inthashCode(boolean value) Returns a hash code for abooleanvalue; compatible withBoolean.hashCode().static booleanlogicalAnd(boolean a, boolean b) Returns the result of applying the logical AND operator to the specifiedbooleanoperands.static booleanlogicalOr(boolean a, boolean b) Returns the result of applying the logical OR operator to the specifiedbooleanoperands.static booleanlogicalXor(boolean a, boolean b) Returns the result of applying the logical XOR operator to the specifiedbooleanoperands.static booleanParses the string argument as a boolean.toString()Returns aStringobject representing this Boolean's value.static StringtoString(boolean b) Returns aStringobject representing the specified boolean.static BooleanvalueOf(boolean b) Returns aBooleaninstance representing the specifiedbooleanvalue.static BooleanReturns aBooleanwith a value represented by the specified string.
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Field Details
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TRUE
TheBooleanobject corresponding to the primitive valuetrue. -
FALSE
TheBooleanobject corresponding to the primitive valuefalse. -
TYPE
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Constructor Details
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Boolean
Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. The static factoryvalueOf(boolean)is generally a better choice, as it is likely to yield significantly better space and time performance. Also consider using the final fieldsTRUEandFALSEif possible.Allocates aBooleanobject representing thevalueargument.- Parameters:
value- the value of theBoolean.
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Boolean
Deprecated, for removal: This API element is subject to removal in a future version.It is rarely appropriate to use this constructor. UseparseBoolean(String)to convert a string to abooleanprimitive, or usevalueOf(String)to convert a string to aBooleanobject.Allocates aBooleanobject representing the valuetrueif the string argument is notnulland is equal, ignoring case, to the string"true". Otherwise, allocates aBooleanobject representing the valuefalse.- Parameters:
s- the string to be converted to aBoolean.
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Method Details
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parseBoolean
Parses the string argument as a boolean. Thebooleanreturned represents the valuetrueif the string argument is notnulland is equal, ignoring case, to the string"true". Otherwise, a false value is returned, including for a null argument.Example:
Boolean.parseBoolean("True")returnstrue.
Example:Boolean.parseBoolean("yes")returnsfalse.- Parameters:
s- theStringcontaining the boolean representation to be parsed- Returns:
- the boolean represented by the string argument
- Since:
- 1.5
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booleanValue
public boolean booleanValue()Returns the value of thisBooleanobject as a boolean primitive.- Returns:
- the primitive
booleanvalue of this object.
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valueOf
Returns aBooleaninstance representing the specifiedbooleanvalue. If the specifiedbooleanvalue istrue, this method returnsBoolean.TRUE; if it isfalse, this method returnsBoolean.FALSE. If a newBooleaninstance is not required, this method should generally be used in preference to the constructorBoolean(boolean), as this method is likely to yield significantly better space and time performance.- Parameters:
b- a boolean value.- Returns:
- a
Booleaninstance representingb. - Since:
- 1.4
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valueOf
Returns aBooleanwith a value represented by the specified string. TheBooleanreturned represents a true value if the string argument is notnulland is equal, ignoring case, to the string"true". Otherwise, a false value is returned, including for a null argument.- Parameters:
s- a string.- Returns:
- the
Booleanvalue represented by the string.
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toString
Returns aStringobject representing the specified boolean. If the specified boolean istrue, then the string"true"will be returned, otherwise the string"false"will be returned.- Parameters:
b- the boolean to be converted- Returns:
- the string representation of the specified
boolean - Since:
- 1.4
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toString
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hashCode
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hashCode
public static int hashCode(boolean value) Returns a hash code for abooleanvalue; compatible withBoolean.hashCode().- Parameters:
value- the value to hash- Returns:
- a hash code value for a
booleanvalue. - Since:
- 1.8
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equals
Returnstrueif and only if the argument is notnulland is aBooleanobject that represents the samebooleanvalue as this object. -
getBoolean
Returnstrueif and only if the system property named by the argument exists and is equal to, ignoring case, the string"true". A system property is accessible throughgetProperty, a method defined by theSystemclass.If there is no property with the specified name, or if the specified name is empty or null, then
falseis returned.- Parameters:
name- the system property name.- Returns:
- the
booleanvalue of the system property. - See Also:
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compareTo
Compares thisBooleaninstance with another.- Specified by:
compareToin interfaceComparable<Boolean>- Parameters:
b- theBooleaninstance to be compared- Returns:
- zero if this object represents the same boolean value as the argument; a positive value if this object represents true and the argument represents false; and a negative value if this object represents false and the argument represents true
- Throws:
NullPointerException- if the argument isnull- Since:
- 1.5
- See Also:
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compare
public static int compare(boolean x, boolean y) Compares twobooleanvalues. The value returned is identical to what would be returned by:Boolean.valueOf(x).compareTo(Boolean.valueOf(y))- Parameters:
x- the firstbooleanto comparey- the secondbooleanto compare- Returns:
- the value
0ifx == y; a value less than0if!x && y; and a value greater than0ifx && !y - Since:
- 1.7
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logicalAnd
public static boolean logicalAnd(boolean a, boolean b) Returns the result of applying the logical AND operator to the specifiedbooleanoperands.- Parameters:
a- the first operandb- the second operand- Returns:
- the logical AND of
aandb - Since:
- 1.8
- See Also:
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logicalOr
public static boolean logicalOr(boolean a, boolean b) Returns the result of applying the logical OR operator to the specifiedbooleanoperands.- Parameters:
a- the first operandb- the second operand- Returns:
- the logical OR of
aandb - Since:
- 1.8
- See Also:
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logicalXor
public static boolean logicalXor(boolean a, boolean b) Returns the result of applying the logical XOR operator to the specifiedbooleanoperands.- Parameters:
a- the first operandb- the second operand- Returns:
- the logical XOR of
aandb - Since:
- 1.8
- See Also:
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describeConstable
Returns anOptionalcontaining the nominal descriptor for this instance.- Specified by:
describeConstablein interfaceConstable- Returns:
- an
Optionaldescribing the Boolean instance - Since:
- 15
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